Scattering of two heavy Fermi polarons: Resonances and quasibound states
| Autor: | Michael Rautenberg, Manfred Salmhofer, Binh Tran, Tilman Enss, Moritz Drescher, Matthias Weidemüller, Manuel Gerken, Eleonora Lippi, Bing Zhu |
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| Rok vydání: | 2020 |
| Předmět: |
Condensed Matter::Quantum Gases
Physics Efimov state Condensed matter physics Scattering FOS: Physical sciences Scattering length Fermion 01 natural sciences 010305 fluids & plasmas Quantum Gases (cond-mat.quant-gas) 0103 physical sciences Bound state Condensed Matter::Strongly Correlated Electrons Condensed Matter - Quantum Gases 010306 general physics Fermi gas Quantum fluctuation Fermi Gamma-ray Space Telescope |
| Zdroj: | Physical Review A. 102 |
| ISSN: | 2469-9934 2469-9926 |
| Popis: | Impurities in a Fermi sea, or Fermi polarons, experience a Casimir interaction induced by quantum fluctuations of the medium. When there is short-range attraction between impurities and fermions, also the induced interaction between two impurities is strongly attractive at short distance and oscillates in space for larger distances. We theoretically investigate the scattering properties and compute the scattering phase shifts and scattering lengths between two heavy impurities in an ideal Fermi gas at zero temperature. While the induced interaction between impurities is weakly attractive for weak impurity-medium interactions, we find that impurities strongly and attractively interacting with the medium exhibit resonances in the induced scattering with a sign change of the induced scattering length and even strong repulsion. These resonances occur whenever a three-body Efimov bound state appears at the continuum threshold. At energies above the continuum threshold, we find that the Efimov state in medium can turn into a quasibound state with a finite decay width. 7 pages, 6 figures; published version |
| Databáze: | OpenAIRE |
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